Studies of the Rate Constant of L-DOPA Oxidation and Decarboxylation by HPLC

The objective of current investigation was to study the degradation behavior of L-DOPA under different conditions by high performance liquid chromatography (HPLC), and to develop and validate a stability-indicating HPLC method. The developed RP-HPLC method was validated with respect to linearity, accuracy, precision and specificity. Oxidation was found to occur in alkaline and to some extent in thermal conditions, while the drug was stable when incubated at acidic conditions and under photolytic stress. The oxidation of L-DOPA was observed to follow first-order kinetics. The degradation rate constants and half-life were calculated. The cytotoxicity and enzymatic degradation of L-DOPA was examined using the human intestinal epithelial Caco-2 cells. The drug was rapidly decarboxylated by aromatic amino acid decarboxylase to dopamine. The conversion of L-DOPA to dopamine was dose - and time-dependent

Determinants of morbidity and mortality following emergency abdominal surgery in children in low-income and middle-income countries

Background: Child health is a key priority on the global health agenda, yet the provision of essential and emergency surgery in children is patchy in resource-poor regions. This study was aimed to determine the mortality risk for emergency abdominal paediatric surgery in low-income countries globally. Methods: Multicentre, international, prospective, cohort study. Self-selected surgical units performing emergency abdominal surgery submitted prespecified data for consecutive children aged <16 years during a 2-week period between July and December 2014. The United Nation's Human Development Index (HDI) was used to stratify countries. The main outcome measure was 30-day postoperative mortality, analysed by multilevel logistic regression. Results: This study included 1409 patients from 253 centres in 43 countries; 282 children were under 2 years of age. Among them, 265 (18.8%) were from low-HDI, 450 (31.9%) from middle-HDI and 694 (49.3%) from high-HDI countries. The most common operations performed were appendectomy, small bowel resection, pyloromyotomy and correction of intussusception. After adjustment for patient and hospital risk factors, child mortality at 30 days was significantly higher in low-HDI (adjusted OR 7.14 (95% CI 2.52 to 20.23), p<0.001) and middle-HDI (4.42 (1.44 to 13.56), p=0.009) countries compared with high-HDI countries, translating to 40 excess deaths per 1000 procedures performed. Conclusions: Adjusted mortality in children following emergency abdominal surgery may be as high as 7 times greater in low-HDI and middle-HDI countries compared with high-HDI countries. Effective provision of emergency essential surgery should be a key priority for global child health agendas